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Term Loan (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	May 20, 2020	Mar. 31, 2020	Mar. 31, 2019	Aug. 31, 2018
Debt Instrument [Line Items]
Interest expense		$ 330	$ 358
Term Loan [Member]
Debt Instrument [Line Items]
Interest expense		330	358
Silicon Valley Bank [Member] \| Term Loan [Member]
Debt Instrument [Line Items]
Amortization of debt discount and accretion of final payment fee		$ 137	$ 125
Silicon Valley Bank [Member] \| Term Loan [Member] \| Loan Agreement [Member]
Debt Instrument [Line Items]
Aggregate principal amount of debt instrument				$ 15,500
Warrants outstanding to purchase common stock		40,000
Warrants exercise price per common share		$ 9.79
Silicon Valley Bank [Member] \| Term Loan [Member] \| Loan Agreement [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument, final payment fee	$ 1,008
Debt instrument prepayment fee	$ 225